Ask HN: How to give feedback?

What's the best way of giving feedback ? Not formal feedback like manager to engineer. But let's say peer evaluation OR face to face to another engineer.

I read Ben's article on Making of a CEO where he mentions about feedback & S* Sandwich. The message I got is that giving feedback is tricky & not one size fits all.

But, I want to hear from this community on how they give feedback to peers in various situations. How do you take care of the personal dynamics involved ? Ben's Article: www.bhorowitz.com/making_yourself_a_ceo